Film forming apparatus, film forming method, and method for manufacturing electronic device

Abstract

Provided is a film forming apparatus capable of forming a film on an object to be formed by sputtering using a rotating target comprising an alloy of two or more components. The film forming apparatus includes: a cylindrical target composed of an alloy of two or more components; and a magnetic field generating member that is provided inside the target so that the angle around a rotation axis parallel to the cylindrical central axis is variable, and that generates a leakage magnetic field that leaks from the outer peripheral surface of the target. A film forming apparatus for forming an alloy thin film by sputtering on a film forming object disposed facing a target while rotating the target, the film forming apparatus being characterized in that the angle of a magnetic field generating member is controlled on the basis of information on the composition ratio of the alloy thin film.

Description

Technical Field

[0001] The present invention relates to a film forming apparatus and method for forming a film on a substrate by sputtering, and a method for manufacturing an electronic device. Background Art

[0002] As a film-forming apparatus for forming thin films of metals or metal oxides on an object such as a substrate, there is a sputtering apparatus that positions a cylindrical target (hereinafter referred to as a rotating target) facing the substrate and performs sputtering while rotating the rotating target. Sputtering apparatuses using rotating targets have the advantage of being able to more uniformly sputter the target surface compared to planar sputtering apparatuses using flat targets. Furthermore, there is a sputtering apparatus using a magnetron sputtering method. This sputtering apparatus creates a magnetic field by placing a magnet inside the rotating target, leaking it to the outside of the rotating target, thereby increasing the plasma density near the surface of the rotating target (Patent Document 1).

[0003] As an example of a film that can be formed by a sputtering device, there is a cathode metal film formed on the organic layer of an organic EL (electroluminescent) element. As the component of the cathode metal film, from the viewpoint of the electron injection property to the organic layer, preferably alkali metals, alkaline earth metals or their alloys with low work functions such as Mg, but from the viewpoint of oxidation resistance, preferably metals with high work functions such as Au, Ag, Al. In order to take into account both electron injection property and oxidation resistance, there is a technology (patent document 2) that forms the cathode metal film by an alloy with Mg and Ag as main components. In patent document 2, a flat target consisting of Mg and a flat target consisting of Ag are set in a chamber, and a voltage is applied to the two targets simultaneously to sputter, and a layer consisting of Mg-Ag alloy is formed on the organic layer. Then, by only applying voltage to the Ag target to sputter, a layer consisting of Ag is formed on the Mg-Ag alloy layer, thereby forming a cathode metal film consisting of a multilayer film with a difference in the composition ratio of Mg and Ag in the film thickness direction.

[0004] Patent Document 3 describes a method for producing a rotary target made of a Mg—Ag alloy.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 2020-200520

[0008] Patent Document 2: Japanese Patent Application Laid-Open No. 2004-200047

[0009] Patent Document 3: Japanese Patent Application Laid-Open No. 2013-204052 Summary of the Invention

[0010] Problems to be solved by the invention

[0011] The sputtering device of Patent Document 2 uses multiple independent flat targets composed of each component of the alloy, but does not describe a sputtering device using a rotating target composed of the alloy. Patent Document 3 describes a rotating target composed of an alloy of two components, but does not describe a sputtering device using this rotating target.

[0012] An object of the present invention is to provide a film forming apparatus capable of forming a film on a film formation object by sputtering using a rotary target composed of an alloy of two or more components.

[0013] Means for solving problems

[0014] The film forming apparatus of the present invention comprises:

[0015] a cylindrical target composed of an alloy of two or more components; and

[0016] a magnetic field generating member disposed inside the target so as to be variable in angle about a rotation axis parallel to the central axis of the cylindrical shape, and generating a leakage magnetic field leaking from the outer peripheral surface of the target;

[0017] The film forming device forms an alloy thin film by sputtering on a film forming object arranged to face the target while rotating the target.

[0018] The film forming apparatus is characterized in that the angle of the magnetic field generating member is controlled based on information on the composition ratio of the alloy thin film.

[0019] The film forming method of the present invention is a film forming method using a film forming apparatus, wherein the film forming apparatus comprises:

[0020] a cylindrical target composed of an alloy of two or more components; and

[0021] a magnetic field generating member disposed inside the target so as to be variable in angle about a rotation axis parallel to the central axis of the cylindrical shape, and generating a leakage magnetic field leaking from the outer peripheral surface of the target;

[0022] The film forming method is characterized by:

[0023] a step of forming an alloy thin film by sputtering on a film formation object disposed opposite to the target while rotating the target; and

[0024] a step of controlling the angle of the magnetic field generating member based on information on the composition ratio of the alloy thin film.

[0025] Effects of the Invention

[0026] According to the present invention, it is possible to provide a film forming apparatus capable of forming a film on a film formation object by sputtering using a rotary target composed of an alloy of two or more components. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a diagram showing the structure of an organic EL element according to an example.

[0028] Figure 2 It is a diagram showing an in-line film forming apparatus according to an embodiment.

[0029] Figure 3 It is a diagram showing a cluster type film forming apparatus according to an embodiment.

[0030] Figure 4 It is a schematic diagram showing the structure of a substrate transport type sputtering apparatus according to an embodiment.

[0031] Figure 5 It is a schematic diagram showing the structure of a substrate transport type sputtering apparatus according to an embodiment.

[0032] Figure 6 It is a schematic diagram showing the structure of the magnet unit of the sputtering device of the embodiment.

[0033] Figure 7 It is a diagram for explaining the angle of the magnet unit of the sputtering device of the embodiment.

[0034] Figure 8 It is a schematic diagram showing the structure of a rotating cathode unit moving type sputtering device according to an embodiment.

[0035] Figure 9 It is a schematic diagram showing the structure of a dual cathode sputtering device according to an embodiment.

[0036] Figure 10 It is a schematic diagram showing the structure of a dual cathode sputtering device according to an embodiment.

[0037] Figure 11 It is a diagram showing the angle of the magnet unit of the dual cathode sputtering device of the embodiment.

[0038] Figure 12 It is a diagram showing the angle of the magnet unit of the dual cathode sputtering device of the embodiment.

[0039] Figure 13 It is a diagram showing the swinging operation of the magnet unit of the sputtering device according to the embodiment.

[0040] Figure 14 This is a diagram showing the relationship between the angle of the magnet unit and the Mg composition ratio in the sputtering device of the Example.

[0041] Figure 15This is a graph showing the difference in the amount of deposition due to the alloy composition in the sputtering apparatus of the Example.

[0042] Figure 16 This is a graph showing the relationship between the sputtering film formation time and the Mg composition ratio in Example 2.

[0043] Figure 17 This is a graph showing the relationship between the sputtering film formation time and the Mg composition ratio in Example 3.

[0044] Figure 18 This is a diagram showing the device region and the inspection region in the substrate of Example 4. DETAILED DESCRIPTION

[0045] Hereinafter, embodiments of the present invention will be described in detail. However, the following embodiments are merely illustrative of the preferred structures of the present invention and do not limit the scope of the present invention to these structures. In addition, the hardware structure and software structure, processing flow, manufacturing conditions, dimensions, materials, shapes, etc. of the device described below, unless otherwise specified, are not intended to limit the scope of the present invention to these. Although multiple features are described in the embodiments, not all of these multiple features are necessary for the invention, and multiple features can also be combined arbitrarily. In addition, in the accompanying drawings, the same or similar structures are marked with the same figure numerals, and repeated descriptions are omitted.

[0046] The film forming apparatus of the present invention is used to deposit and form a thin film on a substrate (including a structure in which a laminate is formed on a substrate) in the manufacture of various electronic devices such as semiconductor devices, magnetic devices, and electronic components, optical components, etc. More specifically, the film forming apparatus of the present invention is preferably used in the manufacture of electronic devices such as light-emitting elements, photoelectric conversion elements, and touch panels. In particular, it is particularly preferably used in the manufacture of organic light-emitting elements such as OLED (Organic Light Emitting Diode), and organic photoelectric conversion elements such as organic thin-film solar cells. It should be noted that the electronic devices in the present invention also include display devices (such as organic EL (Electro-Luminescence: electroluminescence) display devices) or lighting devices (such as organic EL lighting devices) with light-emitting elements, and sensors (such as organic CMOS image sensors) with photoelectric conversion elements. In addition, a method for manufacturing an electronic device having a process of forming a thin film on a substrate using the film forming apparatus of each of the following embodiments or a film forming apparatus that is a modification of the film forming apparatus of each embodiment within the scope of the present invention is also included in the present invention.

[0047] Figure 1The following schematically shows a general layer structure of an organic EL element that can be manufactured using the film-forming apparatus of the following embodiments. An OLED generally has a structure in which an anode 61, an organic light-emitting layer 62, and a cathode 65 are stacked on a substrate 6. The film-forming apparatus of the present invention is suitable for use when forming a cathode 65 on the organic light-emitting layer 62. The cathode 65 is an alloy thin film composed of two metal materials. From the perspective of electron injection into the organic light-emitting layer 62, the first component of the alloy constituting the cathode 65 is an alkali metal or alkaline earth metal with a low work function such as Mg, or an alloy thereof, and from the perspective of oxidation resistance, the second component is a metal with a high work function such as Au, Ag, or Al. In the following embodiments, the first component is Mg and the second component is Ag.

[0048] The cathode 65 is preferably composed of a multilayer film consisting of a first layer 63 and a second layer 64 formed on the first layer 63. This is because it is preferred to increase the Mg composition ratio on the side close to the organic light-emitting layer 62 to improve the electron injection property, and on the other hand, it is preferred to increase the Ag composition ratio on the side close to the external environment to improve the oxidation resistance. By making the cathode 65 a multilayer film with different composition ratios, it is possible to take into account both electron injection property and oxidation resistance. Therefore, although the first layer 63 and the second layer 64 are both Mg-Ag alloys, the Mg composition ratio of the first layer 63 is greater than the Mg composition ratio of the second layer 64, and the Ag composition ratio of the second layer 64 is greater than the Ag composition ratio of the first layer 63. That is, the cathode 65 is composed of a multilayer film in which the composition ratio of the alloy is different in the film thickness direction (the composition ratio has a gradient).

[0049] It should be noted that the alloy constituting the cathode 65 is not limited to this example, and may also be other alloys mainly composed of a first component having excellent electron injection properties and a second component having excellent oxidation resistance. Examples of the first component include Li, Na, Mg, K, Ca, Cs, and Yb. Examples of the second component include Ag and Al.

[0050] Furthermore, the film-forming apparatus of the present invention is not limited to forming cathodes for OLEDs or forming multilayer films with varying alloy composition ratios across the thickness direction, but can be applied to forming conventional films composed of alloys of two or more components. In particular, the present invention is not limited to forming cathodes composed of multilayer films, but can also be applied to forming cathodes composed of single-layer alloy thin films. Furthermore, the film-forming apparatus of the present invention is not limited to forming films on organic films, but can be applied to forming films on a variety of surfaces, as long as the combination of materials capable of forming films by sputtering, such as metal materials or oxide materials, is used.

[0051] The present invention can be applied to Figure 2 The in-line film forming apparatus shown in FIG. Figure 3 Any of the group-type film-forming devices shown.

[0052] Figure 2 This is a diagram schematically showing a portion of an in-line film forming apparatus 100 having a plurality of film forming chambers connected thereto. The film forming apparatus 100 includes film forming chambers 101, 102, 103, and 104, and an inspection chamber 105 at the rear section of the film forming chamber 104. In each film forming chamber, an anode 61, an organic light-emitting layer 62, a first layer 63 of a cathode 65, and a second layer 64 of the cathode 65 are formed. The substrate 6 after film formation in the film forming chamber 104 is fed into the inspection chamber 105 at the rear section. An inspection device (e.g., EPMA (electron probe microanalyzer)) capable of measuring the Mg composition ratio of the alloy thin film is provided in the inspection chamber 105, and composition analysis can be performed on the substrate 6 on which the Mg-Ag alloy thin film is formed in the film forming chamber 104. It should be noted that it is also possible to form both the first layer 63 and the second layer 64 constituting the cathode 65 in one film forming chamber.

[0053] Figure 3 This diagram schematically illustrates a portion of a cluster-type film-forming apparatus 111, comprising multiple connected vacuum chambers. In this film-forming apparatus 111, a first cluster C1, a second cluster C2, and a third cluster C3 are connected in series. In addition to the film-forming chambers 101-104, each cluster also includes known chambers such as a mask stocker, although their description is omitted here. An inspection chamber 105 is located between the second and third clusters C2 and C3. In this inspection chamber 105, the composition of the alloy thin film formed in the second cluster C2 is analyzed.

[0054] Each film forming chamber is provided with a device for forming a film by sputtering or vapor deposition. Hereinafter, an example in which a sputtering device is provided will be described.

[0055] (Substrate transport type sputtering device)

[0056] Reference Figure 4 An example of a sputtering apparatus to which the present invention can be applied will be described. In the following description, a direction parallel to a conveying direction S of a substrate 6 conveyed within the sputtering apparatus 1 is referred to as an X direction, a direction parallel to the rotation axis of a cylindrical target 2 included in the sputtering apparatus 1 is referred to as a Y direction, and a vertically upward direction is referred to as a Z direction. Figure 4 1 is a diagram schematically showing the internal structure of the sputtering device 1 as viewed from the Y direction.

[0057] Figure 4The sputtering device 1 shown has a chamber 10 in which a substrate 6 as a film-forming object and a target 2 are arranged. In the sputtering device 1, the target 2 is arranged below the substrate 6 in the vertical direction, and film formation based on upward deposition is performed with the film-forming surface of the substrate 6 facing downward in the vertical direction. It should be noted that the present invention is not limited to this, and a structure in which the target 2 is arranged above the substrate 6 in the vertical direction, and film formation based on downward deposition is performed with the film-forming surface of the substrate 6 facing upward in the vertical direction may also be employed. In addition, a structure in which the substrate 6 is vertically erected and film formation is performed with the film-forming surface of the substrate 6 parallel to the vertical direction may also be employed.

[0058] The rotating cathode unit 8 has a target 2 as a cylindrical rotating target and a magnet unit 3 as a magnetic field generating member that is arranged in a hollow portion inside the target 2 and generates a magnetic field on the periphery of the target 2. A liner 2a is provided inside the target 2. The rotating cathode unit 8 is fixed relative to the chamber 10, and the target 2 is supported relative to the chamber 10 so as to be rotatable around the central axis of the cylinder. The target 2 rotates in the direction of arrow R by transmitting the driving force of the target driving device 11 through a drive transmission member such as a gear. Arrow R is in the same direction as Figure 4 The Y direction is shown in a clockwise direction in the cross section perpendicular to the Y direction.

[0059] The target 2 is composed of a film forming material for forming a film on the substrate 6 by sputtering, and functions as a supply source of the film forming material. Figure 1 The following describes an example in which a cathode 65 (upper electrode) made of a Mg-Ag alloy is formed by sputtering on a substrate 6 of an OLED anode 61 and an organic light-emitting layer 62. Therefore, the material constituting the target 2 is an alloy of two components, Ag and Mg.

[0060] A layer formed of the film-forming material of the target 2 is formed on the outside of the liner 2a. A power supply 13 is connected to the liner 2a, which functions as a cathode to which a negative voltage is applied from the power supply 13. It should be noted that the voltage can also be applied directly to the target 2. In this case, the structure can also be configured without the liner 2a. The power supply 13 uses a DC power supply, an AC power supply or a high-frequency power supply according to the material of the target 2. The chamber 10 is grounded. In addition, the target 2 is a cylindrical target, but the "cylindrical" mentioned here not only means a mathematically strict cylindrical shape, but also includes a cylindrical shape whose main line is not a straight line but a curve, and a cylindrical shape whose cross section perpendicular to the central axis is not a mathematically strict "circle". That is, the target 2 in the present invention can be any cylindrical shape as long as it can rotate around the central axis.

[0061] The magnetic field is formed on a portion of the surface side of the target 2 by the magnet unit 3. The magnet unit 3 is arranged inside the target 2 in such a manner that the angle around the central axis parallel to the cylindrical central axis of the target 2 is variable. The magnet unit 3 is supported so as to be rotatable relative to the central axis. The magnet unit 3 transmits the driving force of the magnet driving device 110 through a drive transmission member such as a gear, as shown by the arrow M. Figure 4 The target 2 rotates clockwise and counterclockwise in the cross section perpendicular to the Y direction. The magnet unit 3 can be stationary at any angle. The rotation of the target 2 by the target drive device 11 and the rotation of the magnet unit 3 by the magnet drive device 110 are independently controlled.

[0062] The substrate 6 is introduced through a gate valve 17 provided on one side wall of the chamber 10. The substrate 6 is transported horizontally (in the direction indicated by arrow S) within the chamber 10 by a transport member 120, and a film is formed by sputtering. After the film is formed on the entire film formation surface of the substrate 6, the substrate 6 is discharged through a gate valve 18 provided on the other side wall of the chamber 10.

[0063] A gas introduction member 16 and an exhaust member 15 are connected to the chamber 10, creating a structure capable of regulating the interior to a predetermined pressure. Sputtering gas (an inert gas such as argon, or a reactive gas such as oxygen or nitrogen) is introduced into the chamber 10 by the gas introduction member 16 through an inlet 41 provided in the chamber 10. Furthermore, the exhaust member 15, such as a vacuum pump, exhausts the interior of the chamber 10 through the exhaust port 5. This maintains the predetermined pressure within the chamber 10.

[0064] The gas introduction member 16 has an introduction port 41, which is composed of a supply source such as a gas cylinder (not shown), a piping system connecting the supply source and the introduction port 41, various vacuum valves, a mass flow controller, etc. provided in the piping system, and the supply amount can be adjusted by a flow control valve of the mass flow controller. The flow control valve has an electrically controllable structure such as a solenoid valve. The introduction port 41 is arranged on the vertical side wall of the chamber 10. It should be noted that the setting position of the introduction port 41 is not limited to the side wall, and can also be set on the bottom wall or the top wall. In addition, the piping can also extend into the chamber 10, and the introduction port can open in the chamber 10. In addition, it can also be configured so that a plurality of introduction ports 41 are provided, and they are arranged along the rotation axis direction of the target 2.

[0065] The exhaust component 15 has a vacuum pump and a piping system connecting the vacuum pump to the exhaust port 5. The piping system is provided with an electrically controllable flow control valve such as a conductance valve, and the exhaust volume can be adjusted by the control valve. The exhaust port 5 is provided on the bottom wall of the chamber 10. It should be noted that the location of the exhaust port 5 is not limited to the bottom wall, and can also be provided on a vertical side wall or on the top wall. In addition, the piping can also extend into the chamber 10, and the exhaust port 5 can open in the chamber 10.

[0066] While the angle of the magnet unit 3 is fixed, the control unit 14 controls the target drive device 11 to rotate the target 2 in the direction of arrow R, and controls the power supply 13 to apply a negative voltage to the target 2. When a voltage is applied to the target 2, the area where the magnetic field generated by the magnet unit 3 exists becomes the sputtering area A where plasma is concentrated and sputtered particles are generated. During the film formation process, since the magnet unit 3 is stationary relative to the chamber 10, the angle between the sputtering area A and the film formation surface of the substrate 6 is fixed during the film formation process. The inert gas ions in the positive ion state in the plasma collide with the surface of the target 2, and the atoms and molecules of the material constituting the target 2 are ejected from the target 2. The particles of the film forming material emitted from the target 2 adhere to and accumulate on the film formation surface of the substrate 6.

[0067] Here, the relative angle between the sputtering area A and the film forming target surface of the substrate 6 is defined, for example, as the angle formed by the line segment that divides the central angle of the arc corresponding to the sputtering area A on the cylindrical surface of the target 2 into two equal parts within an imaginary plane perpendicular to the rotation axis of the target 2 and the imaginary plane including the film forming target surface of the substrate 6.

[0068] The substrate 6 is moved horizontally (indicated by arrow S) by the transport member 120. As a result, the film formation target area on the substrate 6 facing the sputtering area A moves horizontally. Consequently, film formation is sequentially performed on the film formation target surface of the substrate 6 from the downstream end toward the upstream end in the transport direction S. Consequently, sputtering film formation is uniformly performed over the entire surface of the substrate 6.

[0069] The area on the surface of the target 2 where sputtered particles are emitted moves in the circumferential direction as the target 2 rotates. Therefore, if attention is paid to a certain local area on the surface of the target 2, sputtering is performed intermittently at a cycle determined by the rotation speed of the target 2.

[0070] Figure 5 This figure schematically illustrates the internal structure of the sputtering apparatus 1 as viewed from the X direction. The Y-direction end of the target 2 is rotatably supported by a support block 210 and an end block 220. A power transmission mechanism is provided on the support block 210 and the end block 220 to transmit the driving force from the target drive device 11, which serves as a rotational drive device, to the target 2. The target drive device 11 includes a drive source such as a motor and rotationally drives the target 2 via the power transmission mechanism.

[0071] Figure 6 This figure schematically illustrates the structure of the magnet unit 3 disposed within the target 2. The magnet unit 3 comprises a central magnet 31 extending parallel to the target 2's rotation axis, peripheral magnets 32 surrounding the central magnet 31 and having opposite polarities, and a yoke plate 33. The peripheral magnets 32 consist of a pair of straight portions 32a and 32b extending parallel to the central magnet 31, and deflection portions 32c and 32d connecting the ends of the straight portions 32a and 32b. The magnetic field generated by the magnet unit 3 includes magnetic lines of force that loop back from the magnetic poles of the central magnet 31 toward the straight portions 32a and 32b of the peripheral magnets 32. This creates a circular magnetic field tunnel extending along the target 2's rotation axis near the surface of the target 2. This magnetic field captures electrons, concentrating plasma near the target 2's surface and improving sputtering efficiency. The magnetic field of the magnet unit 3 forms a high-density plasma, and the area where sputtered particles are concentrated is designated as sputtering area A.

[0072] The magnet unit 3 is fixed to a base 34, to which a rotation shaft 35 is fixed. The rotation shaft 35 extends parallel to the central axis of the cylindrical target 2, rotatably supports the base 34 relative to the chamber 10, and is rotated by the driving force of the magnet drive 110. Thus, the magnet unit 3 is supported for rotation relative to the central axis, and the angle around the rotation shaft 35, which is parallel to the cylindrical central axis of the target 2, is variable. The rotational movement of the magnet unit 3 is achieved by the driving force of the magnet drive 110. The magnet drive 110 is configured to rotate the magnet unit 3 to any angle and then stop it at that angle. This allows sputtering to be performed while the magnet unit 3 is stationary during film formation, or, as described later, to be swung during film formation, or to change the angle of the magnet unit 3 to control the composition ratio when film formation is not in progress. While the sputtering apparatus 1 is described with an example in which the central axis of the rotation shaft 35 coincides with the central axis of the target 2, the central axis of the rotation shaft 35 can be parallel to the central axis of the target 2. The driving force of the magnet driving device 110 is transmitted to the rotating shaft 35 via a power transmission mechanism (not shown). The magnet driving device 110 includes a driving source such as a motor.

[0073] Figure 7 The positional relationship among the substrate 6 , the target 2 , and the magnet unit 3 is shown when a film is formed by sputtering upward deposition using the cylindrical target 2 on a vertically lower surface of the substrate 6 disposed above the target 2 .

[0074] When sputtering gas ions (e.g., Ar+) generated by applying a negative voltage to the target 2 collide with the surface of the target 2, atoms and molecules of the film-forming material constituting the target 2 are emitted from the target 2 as sputtered particles. The location and direction of emission of these emitted substances (sputtered particles) from the surface of the target 2 during sputtering can be set by the magnetic field formed near the surface of the target 2 by the magnet unit 3.

[0075] exist Figure 7 , the rotation center O of the target 2 coincides with the rotation center of the rotation axis 35 of the magnet unit 3. Sputtered particles are concentratedly generated in the sputtering area A defined by the positions of the line segments D2 and D3 passing through the rotation center of the rotation axis 35 of the magnet unit 3 and the positions between the central magnet 31 and the peripheral magnets 32. It should be noted that the sputtering area A may also be an area determined based on the magnetic flux distribution of the magnetic field formed by the magnet unit 3. In addition, it may also be an area on the surface of the target 2 where the magnetic field intensity has a value greater than a certain value. In addition, the configuration and structure of the magnets serving as the magnet unit 3, the position where the sputtered particles are concentratedly generated, and the direction in which the emitted materials are emitted from the surface of the target 2 during sputtering may also be determined based on general, statistical, empirical, or experimentally observed phenomena.

[0076] The angle θ of the line segment D1 passing through the rotation center of the rotation axis 35 of the magnet unit 3 and the center of the sputtering area A is defined as the angle of the magnet unit 3. The angle θ of the magnet unit 3 is determined by the position where the line segment D1 is perpendicular to the film formation target surface of the substrate 6 (the magnet unit 3 is located at Figure 7 The position shown by the dotted line in the middle is the reference angle. Figure 7 The clockwise direction is positive.

[0077] (Cathode moving sputtering device)

[0078] Reference Figure 8 Another example of a sputtering apparatus to which the present invention can be applied will be described. Elements common to the above-described substrate transport type sputtering apparatus are given common names and reference numerals, and detailed descriptions thereof will be omitted.

[0079] Figure 8 The sputtering apparatus 1X shown is a sputtering apparatus in which a substrate 6 is fixed to a chamber 10 and a rotary cathode unit 8X is reciprocatingly movable within the chamber 10 . Figure 8 1 is a diagram schematically showing the internal structure of the sputtering apparatus 1X as viewed from a direction (referred to as the Y direction) parallel to the rotation axis of the cylindrical target 2 included in the sputtering apparatus 1X.

[0080] exist Figure 4In the sputtering device 1, the rotating cathode unit 8 does not move relative to the chamber 10, and the substrate 6 moves relative to the chamber 10, thereby forming a film on the film forming target surface of the substrate 6 starting from the end on the downstream side of the conveying direction of the substrate 6. Figure 8 In the sputtering device 1X, the rotating cathode unit 8X moves relative to the chamber 10, and the substrate 6 does not move relative to the chamber 10, and film formation is performed on the film formation target surface of the substrate 6 starting from the end on the upstream side of the moving direction of the rotating cathode unit 8X.

[0081] The rotary cathode unit 8X includes a moving stage 230, and a partition member 260 disposed around the target 2 is provided on the moving stage 230. The partition member 260 is open in the direction in which the substrate 6 is disposed (vertically upward).

[0082] The movable table 230 is supported so as to be movable in the horizontal direction (indicated by arrow T) along a pair of guide rails 250 via conveying guides such as linear bearings. The guide rails 250 are arranged parallel to the X direction. The movable table 230 is driven linearly in the X direction by the linear drive device 12. The linear drive device 12 can use various well-known linear motion mechanisms such as a screw feed mechanism using a ball screw or the like that converts the rotational motion of a rotary motor into linear motion, a linear motor, etc. Therefore, the rotating cathode unit 8X moves in the X direction in the XY plane, and the target 2 moves in the X direction in the XY plane while rotating around a rotation axis parallel to the Y direction.

[0083] When the substrate 6 is introduced into the chamber 10, it is held vertically above the rotating cathode unit 8X by the holder 6a. During film formation, the substrate 6 does not move relative to the chamber 10, while the rotating cathode unit 8X moves horizontally (indicated by arrow T) to form a film by sputtering. After the film is formed on the entire surface of the substrate 6 to be film-formed, the substrate 6 is removed from the chamber 10 through a gate valve 18 provided on the other side wall.

[0084] When film formation is performed by sputtering in the sputtering apparatus 1X, the control unit 14 controls the target driving device 11 to rotationally drive the target 2 in the direction of arrow R, and controls the power supply 13 to apply a negative voltage to the target 2 .

[0085] Since the rotating cathode unit 8X is moved relative to the chamber 10 in the direction of arrow T by the linear drive device 12, the sputtering area A moves relative to the chamber 10 in the direction of arrow T. Furthermore, since the magnet unit 3 does not rotate with the target 2 during film formation, the angle between the sputtering area A and the film formation surface of the substrate 6 remains constant during film formation. During film formation, the substrate 6 is held by the holder 6a and does not move relative to the chamber 10.

[0086] The rotating cathode unit 8X is moved in the horizontal direction by the linear drive device 12, whereby the sputtering area A of the target 2 moves relative to the chamber 10 along the film formation target surface of the substrate 6 along with the movement of the rotating cathode unit 8X. Thus, on the film formation target surface of the substrate 6, as the rotating cathode unit 8X moves, films are sequentially formed from the upstream end toward the downstream end in the movement direction T of the rotating cathode unit 8X.

[0087] (Dual cathode sputtering device)

[0088] Reference Figure 9 、 Figure 10 Another example of a sputtering apparatus to which the present invention is applicable will be described. Elements common to the above-described single cathode sputtering apparatuses 1 and 1X are given the same names and reference numerals, and detailed descriptions thereof will be omitted.

[0089] Figure 9 1 is a diagram schematically showing the internal structure of the sputtering apparatus 1Y as viewed from a direction (referred to as the Y direction) parallel to the rotation axis of the cylindrical second target 2R included in the sputtering apparatus 1Y. Figure 10 1 is a diagram schematically showing the internal structure of the sputtering apparatus 1Y as viewed from a direction (referred to as the X direction) parallel to the moving direction T of the rotary cathode unit 8Y moving in the sputtering apparatus 1Y.

[0090] Figure 9 The sputtering device 1Y and Figure 8 Similarly, in the sputtering device 1X, the rotating cathode unit 8Y moves relative to the chamber 10, and the substrate 6 does not move relative to the chamber 10, and film formation is performed on the film formation target surface of the substrate 6 starting from the end on the upstream side of the moving direction of the rotating cathode unit 8Y.

[0091] Figure 4 The rotating cathode unit 8 of the sputtering device 1 is composed of a cylindrical target 2 and a magnet unit 3. Figure 9 The rotating cathode unit 8Y of the sputtering device 1Y is composed of a cylindrical first target 2L, a first magnet unit 3L as a first magnetic field generating member, a cylindrical second target 2R, and a second magnet unit 3R as a second magnetic field generating member. The first magnet unit 3L is arranged inside the first target 2L in a manner that can be changed in angle around a rotation axis parallel to the central axis of the cylinder, and generates a leakage magnetic field leaking from the outer peripheral surface of the first target 2L. The second magnet unit 3R is arranged inside the second target 2R in a manner that can be changed in angle around a rotation axis parallel to the central axis of the cylinder, and generates a leakage magnetic field leaking from the outer peripheral surface of the second target 2R. The structure of the first target 2L and the first magnet unit 3L, and the structure of the second target 2R and the second magnet unit 3R are similar to Figure 4The target 2 and magnet unit 3 of the sputtering apparatus 1 are identical in structure, but the rotation directions of the first target 2L and the second target 2R by the target driving device 11Y are opposite to each other. The first target 2L rotates in the direction of arrow L, and the second target 2R rotates in the direction of arrow R, which is opposite to the direction of arrow L. The first magnet unit 3L and the second magnet unit 3R rotate as indicated by arrows ML and MR by the driving force of the magnet driving device 110Y.

[0092] The structure in which the rotary cathode unit 8Y can move in the chamber 10 is similar to Figure 8 The rotating cathode unit 8Y has a movable table 230, and a support block 210 and an end block 220 that support the first target 2L and the second target 2R so as to be rotatable. On the movable table 230, the first target 2L and the second target 2R are arranged in a row in the moving direction T (parallel to the X direction) of the rotating cathode unit 8Y. A partition component 260 is provided on the movable table 230 so as to surround the first target 2L and the second target 2R. It should be noted that Figure 10 In order to avoid complication, description of the partition member 260 is omitted. The partition member 260 is open in the direction in which the substrate 6 is arranged (vertically upward).

[0093] When film formation is performed by sputtering in the sputtering device 1Y, the control unit 14 controls the target driving device 11Y to rotate and drive the first target 2L and the second target 2R in the directions of arrows L and R, respectively, and controls the power supply 13 to apply a negative voltage to the first target 2L and the second target 2R. The method of film formation by sputtering is similar to that of Figure 8 The sputtering device 1X is the same.

[0094] Figure 11 Yes Figure 9 FIG. 1 is a diagram showing the positional relationship between the first magnet unit 3L, the second magnet unit 3R, the first target 2L, the second target 2R, and the substrate 6 of the sputtering device 1Y. Figure 11 In the example, the rotation center O of the first target 2L coincides with the rotation center of the rotation axis 35L of the first magnet unit 3L. Sputtered particles are concentrated in the sputtering area AL defined by the positions of line segments D2L and D3L passing through the rotation center of the rotation axis 35L of the first magnet unit 3L and the positions between the central magnet 31L and the peripheral magnets 32L. Furthermore, the rotation center O of the second target 2R coincides with the rotation center of the rotation axis 35R of the second magnet unit 3R. Sputtered particles are concentrated in the sputtering area AR defined by the positions of line segments D2R and D3R passing through the rotation center of the rotation axis 35R of the second magnet unit 3R and the positions between the central magnet 31R and the peripheral magnets 32R.

[0095] The angle θL of the line segment D1L passing through the rotation center of the rotation axis 35L of the first magnet unit 3L and the center of the sputtering area AL is defined as the angle of the first magnet unit 3L. In addition, the angle θR of the line segment D1R passing through the rotation center of the rotation axis 35R of the second magnet unit 3R and the center of the sputtering area AR is defined as the angle of the second magnet unit 3R. The angles θL and θR of the first magnet unit 3L and the second magnet unit 3R are defined as the positions of the line segments D1L and D1R perpendicular to the film forming surface of the substrate 6 (the first magnet unit 3L and the second magnet unit 3R are located at the same position). Figure 11 The position shown by the dotted line is the reference angle. Figure 11 The clockwise direction is positive.

[0096] The first and second targets 2L and 2R are made of Mg-Ag alloy with the same composition, and the first and second magnet units 3L and 3R have the same angles θL and θR. That is, the line segment D1L of the first and second magnet units 3L and 3R face the same direction.

[0097] It should be noted that if Figure 12 As shown, the angles θL and θR of the first magnet unit 3L and the second magnet unit 3R may be set to be equal in absolute value and opposite in sign. In this case, the line segment D1L of the first magnet unit 3L and the line segment D1R of the second magnet unit 3R are symmetrically oriented in the moving direction T (X direction) of the rotating cathode unit 8Y.

[0098] The outer diameters of the first target 2L and the second target 2R are 140 mm, and the distance between the centers of the first target 2L and the second target 2R is 300 mm.

[0099] It should be noted that Figure 9 The dual cathode sputtering device 1Y is a structure in which two cathodes are provided in a rotating cathode unit movable sputtering device. However, the present invention can also be applied to a sputtering device of the dual cathode type. Figure 4 Like the sputtering apparatus 1 of FIG. 1 , a dual-cathode sputtering apparatus including two cathodes is used in a substrate transport type sputtering apparatus.

[0100] (Magnet unit swing type sputtering device)

[0101] Reference Figure 13 Another example of a sputtering apparatus to which the present invention can be applied will be described. Elements common to the single cathode sputtering apparatus 1 described above are given the same names and reference numerals, and detailed descriptions thereof will be omitted.

[0102] exist Figure 4In the sputtering apparatus 1 of FIG. 1 , an example is shown in which the angle θ of the magnet unit 3 is adjusted before film formation begins, and the magnet unit 3 is kept stationary at the adjusted angle θ during film formation. Alternatively, the magnet unit 3 may be swung within a small angle range around the adjusted angle θ during film formation.

[0103] Figure 13 : is a diagram showing the operation when the magnet unit 3 is swung. Figure 13 In the figure, the magnet unit 3, shown by the solid line, is positioned at an angle θ, as indicated by line segment D1, determined before film formation begins. As shown by the dashed line, during film formation, the magnet unit 3 continuously swings between a first position, indicated by line segment D11, and a second position, indicated by line segment D12, with angle θ as the center, within a range of angle δ. That is, during film formation, line segment D1 of the magnet unit 3 swings within a range of θ-δ / 2 degrees to θ+δ / 2 degrees. This makes it possible to even out uneven stacking caused by the shape and arrangement of magnets such as the central magnet 31 and peripheral magnets 32 that constitute the magnet unit 3.

[0104] As will be described later, since the angle θ of the magnet unit 3 affects the composition ratio of the deposited alloy thin film, the swing range of angle δ is preferably small. For example, the swing range is within ±5 degrees around the initial angle θ. In this case, during the film formation process, the magnet unit 3 swings within a range of θ-5 degrees to θ+5 degrees.

[0105] (Relationship between Mg composition ratio and angle of magnet unit)

[0106] Next, the control of the Mg composition ratio by adjusting the angle of the magnet unit, which is a feature of the present invention, will be described.

[0107] In this embodiment, a cylindrical sputtering target made of an alloy material of Ag and Mg is used as the target 2. The composition ratio of Mg in the Mg-Ag alloy target is approximately 10 vol.%.

[0108] The manufacturing method of the target 2 is described. After melting and alloying Ag with a purity of 99.9% or more and Mg with a purity of 99.9% or more, the molten metal is dropped from the bottom of the crucible and an inert gas such as argon is blown to produce Mg-Ag alloy atomized powder. The particle size of the atomized powder is not less than 1 μm and not more than 1000 μm. By blowing the atomized powder together with the high-speed inert gas into the liner 2a, a cylindrical target 2 composed of Mg-Ag alloy is produced. As the liner 2a, stainless steel (SUS304, SUS630, etc.) or titanium, etc. can be used.

[0109] In this embodiment, an Mg-Ag alloy target is used. However, depending on the intended purpose, alloys or compounds containing Cu, Al, Ti, Mo, Cr, Ag, Au, Ni, etc. may also be used. When used in an OLED cathode, examples of the first component include Li, Na, Mg, K, Ca, Cs, and Yb. Examples of the second component include Ag and Al. The Mg-Ag alloy target can be manufactured using methods other than spraying atomized powder and can be produced using casting, spraying, sintering, and other methods.

[0110] The cylindrical target 2 made of Mg-Ag alloy is placed in the sputtering device 1 and a film is formed on the substrate 6. Figure 4 In the sputtering apparatus 1, a magnet unit 3 is disposed (inside the liner tube 2a) and can be oriented at any angle. Before film formation begins, the magnet unit 3 is adjusted to a predetermined angle θ. Sputtering film formation is performed while the target 2 is rotated at 10 rpm at a fixed angle.

[0111] The Ar gas pressure during sputtering is 0.6 Pa, and the temperature of the substrate 6 is room temperature. Figure 7 ) transports the substrate 6 for film formation.

[0112] The composition of the deposited alloy thin films was analyzed using X-ray fluorescence. While X-ray fluorescence analysis was performed here, other methods for analyzing the composition of alloy thin films include XRF (X-ray fluorescence), EDS (energy dispersive X-ray spectroscopy), EPMA (electron probe microanalyzer), XPS (X-ray photoelectron spectroscopy), SIMS (secondary ion mass spectrometry), GDMS (glow discharge mass spectrometry), and ICP (inductively coupled plasma mass spectrometry). Transmission spectroscopy, reflectance spectroscopy, emission spectroscopy, and spectroscopic ellipsometry can also be used.

[0113] The inventors have found in the course of their dedicated research that when the angle θ of the magnet unit 3 in the liner tube 2a is changed to various angles for film formation, the Mg composition ratio of the formed alloy film changes according to the angle θ. For example, when the angle θ of the magnet unit 3 is set to 0 degrees for film formation, the Mg composition ratio is 7.9 vol.%. On the other hand, when the angle θ of the magnet unit 3 is tilted to 20 degrees and 40 degrees for film formation, the Mg composition ratios are 8.4 vol.% and 9.4 vol.%, respectively. The results are shown in FIG. Figure 14 As shown. Figure 14In the figure, the horizontal axis represents the angle θ of the magnet unit 3, and the vertical axis represents the Mg composition ratio of the formed alloy film. As shown in the results, the larger the angle θ of the magnet unit 3, the larger the Mg composition ratio of the Mg-Ag alloy film. That is, the magnet unit 3 of this embodiment is configured so that the larger the angle from the reference position (θ = 0 degrees), the larger the Mg composition ratio of the alloy film. The fact that the Mg composition ratio of the Mg-Ag alloy film shows such a trend is a new insight obtained by the inventors through their dedicated research. In this embodiment, it is characterized in that, based on this insight, the Mg composition ratio of the Mg-Ag alloy film is controlled by adjusting the angle θ of the magnet unit 3.

[0114] The present inventors verified the aforementioned relationship between the angle θ of the magnet unit 3 and the Mg composition ratio of the formed Mg-Ag alloy thin film from the following perspective. With the angle θ of the magnet unit 3 set to 0 degrees and the substrate 6 positioned stationary directly above the cylindrical target 2 for sputtering deposition, the distribution of the accumulation of Ag and Mg on the substrate 6 was examined. Figure 15 Indicates the result. Figure 15 In FIG, the horizontal axis represents the distance from the position where the deposition amount (film thickness) is the largest in the substrate 6 (hereinafter referred to as the maximum film thickness position). In this embodiment, the maximum film thickness position is Figure 7 The intersection of the line segment D1 and the substrate 6 when θ=0 is the position closest to the rotation center O of the target 2. The vertical axis represents the value after the film thickness is normalized by the film thickness at the maximum film thickness position. Figure 15 As shown, the film thickness of both Mg and Ag decreases as the distance from the maximum film thickness position increases. Furthermore, the change (decrease) in film thickness of Mg due to the distance from the maximum film thickness position is more gradual than that of Ag. That is, the accumulation distribution of Mg has a wider mountain shape with a lower peak value than that of Ag. This indicates that the composition ratio of Mg is relatively higher at the wide-angle side (position farther from the maximum film thickness position) compared to the maximum film thickness position, which matches the result that the Mg composition ratio increases when the angle θ of the magnet unit 3 is increased during film transport as described above.

[0115] Thus, in magnetron rotary sputtering using an Mg-Ag alloy target, the Mg composition ratio of the formed alloy thin film can be controlled by changing the angle θ of the magnet unit 3. Based on this knowledge, by controlling the sputtering apparatus 1 and the sputtering film forming process, a Mg-Ag alloy thin film having a desired Mg composition ratio can be stably formed.

[0116] Note that, when the angle θ of the magnet unit 3 is changed, not only the composition ratio but also the film thickness (film formation rate) changes. However, a desired film thickness can be obtained by adjusting the applied voltage of the target 2 and the height of the magnet.

[0117] The above insights are not limited to Mg-Ag alloy targets. Figure 15 As shown, it can also be applied to a magnetron rotary sputtering device using the following alloy target, wherein the alloy target is mainly composed of two materials whose film thickness changes differently depending on the distance from the maximum film thickness position when magnetron rotary sputtering is performed. In other words, as long as the target 2 is composed of an alloy of two or more components, when a film is formed on a film-forming object using the target 2, the accumulation amount distribution of the first component is a combination of two components with a wide mountain shape and a low peak compared to the accumulation amount distribution of the second component. Moreover, when the magnet unit 3 is configured so that the larger the angle from the reference position (θ = 0 degrees), the larger the composition ratio of the first component of the alloy thin film, the control unit 14 increases the angle θ of the magnet unit 3 when the composition ratio of the first component is increased, and decreases the angle θ of the magnet unit 3 when the composition ratio of the first component is decreased based on the composition ratio information of the alloy thin film.

[0118] It should be noted that, as shown in this embodiment, when the structure of the magnet unit 3 and the definition of the angle θ are such that the larger the absolute value of the angle starting from the reference position, the larger the composition ratio of Mg (first component), the control unit 14 increases the absolute value of the angle θ of the magnet unit 3 when the composition ratio of Mg (first component) is increased, and decreases the absolute value of the angle θ of the magnet unit 3 when the composition ratio of Mg (first component) is decreased based on the composition ratio information of the alloy film.

[0119] The relationship between the angle θ of the magnet unit 3 and the Mg composition ratio may not necessarily be the same depending on various conditions such as the shape, arrangement, and magnetic properties of each magnet constituting the magnet unit 3, the arrangement of the magnet unit 3 in the target 2, the composition and composition ratio of the alloy constituting the target 2, the definition of the angle θ of the magnet unit 3, and the positional relationship between the target 2 and the substrate 6. Figure 14 In this case, according to the concept disclosed in the present invention, the relationship between the angle θ of the magnet unit 3 and the Mg composition ratio in the actual sputtering device 1 is used to adjust the angle θ of the magnet unit 3 based on the composition ratio information of the alloy thin film to be formed, thereby also being able to control the Mg composition ratio with high precision.

[0120] <Specific control example>

[0121] When film formation is performed by sputtering in the sputtering apparatus 1, the control unit 14 obtains information about the composition ratio of the alloy thin film formed on the substrate 6 from the composition ratio acquisition unit 130. Examples of the information acquired by the composition ratio acquisition unit 130 include information about the target composition ratio of the alloy thin film formed on the substrate 6, information about the composition ratio of the alloy material constituting the target 2, information about the composition ratio of alloy thin films previously formed in the sputtering apparatus 1 as measured by an inspection device located outside the sputtering apparatus 1, information about the relationship between the angle of the magnet unit 3 and the composition ratio, and information about changes in the composition ratio caused by the passage of time and the number of films formed during long-term continuous film formation. Examples of methods by which the composition ratio acquisition unit 130 acquires information related to this composition ratio include user input, acquisition of information from an external measurement device or experimental equipment via a wired or wireless communication path, acquisition of information via a recording medium, and acquisition of information by reading an optical recognition pattern.

[0122] Based on the information on the composition ratio, the control unit 14 adjusts the angle of the magnet unit 3 before film formation begins. Several embodiments of the method for controlling the composition ratio by adjusting the angle of the magnet unit 3, which is a characteristic of the present invention, will be described below.

[0123] <Example 1>

[0124] As the angle control of the magnet unit 3 based on the composition ratio information, it is possible to consider adjusting the angle θ of the magnet unit 3 according to the Mg composition ratio of the film formation target and the Mg composition ratio of the target 2. The relationship between the angle θ of the magnet unit 3 and the Mg composition ratio can be determined by experiments, for example. Figure 14 The control unit 14 determines the angle θ of the magnet unit 3 during actual film formation based on the target Mg composition ratio, the Mg composition ratio of the target 2 , and the previously acquired relationship between the angle θ of the magnet unit 3 and the Mg composition ratio.

[0125] For example, consider the case where the Mg-Ag alloy thin film of the first layer 63 of the cathode 65 is formed by magnetron rotary sputtering. The Mg composition ratio of the target 2 is set to 10 vol.%, and the target value of the Mg composition ratio of the first layer 63 is set to 9 vol.%. In this case, according to Figure 14 As shown in the graph of FIG. 1 , by setting the angle θ of the magnet unit 3 to about 30 degrees for film formation, the first layer 63 having the target Mg composition ratio can be formed.

[0126] Alternatively, the Mg composition ratio of the first layer 63 actually formed can be analyzed and measured, and the angle θ of the magnet unit 3 can be fine-tuned based on the result to bring the Mg composition ratio closer to the target value. For example, the angle θ of the magnet unit 3 can be adjusted so that the difference from the target Mg composition ratio is 0.5% or less.

[0127] <Example 2>

[0128] As an example of controlling the angle of the magnet unit 3 based on composition ratio information, a control method that provides feedback of information on the Mg composition ratio of a thin film formed on a previous substrate 6 can be considered. In this control, when films are continuously formed on multiple substrates 6, the angle θ of the magnet unit 3 is periodically adjusted to maintain the Mg composition ratio at a target value over a long period of time.

[0129] First, as the first film formation, film formation is performed with the magnet unit 3 in the cylindrical target 2 facing vertically upward (angle θ = 10 degrees). The Mg-Ag alloy thin film formed by this first film formation is subjected to composition analysis by fluorescent X-ray analysis to determine the first Mg composition ratio. Based on the difference between the first Mg composition ratio and the target Mg composition ratio, the angle θ of the magnet unit 3 is changed. After changing the angle θ of the magnet unit 3, the second film formation is performed. By appropriately changing the angle θ of the magnet unit 3, the Mg composition ratio of the Mg-Ag alloy thin film obtained in the second film formation can be brought close to the target Mg composition ratio.

[0130] For example, if the target value of the Mg composition ratio is 9 vol.%, and the Mg composition ratio of the alloy thin film obtained by the first film formation is 8.4 vol%, based on the information of the difference between the measured evaluation value and the target value, the angle θ of the magnet unit 3 is changed to increase by 10 degrees, for example, and the second film formation is performed. The amount of change in the angle θ of the magnet unit 3 can be based on the previously evaluated value through experiments, etc. Figure 14 The relationship between the angle θ of the magnet unit 3 and the Mg composition ratio is determined based on the relationship between the angle θ of the magnet unit 3 and the Mg composition ratio. The relationship between the angle θ of the magnet unit 3 and the Mg composition ratio is pre-stored in the memory of the control unit 14 as a function or table. Based on this relationship read from the memory and the difference between the target value obtained through measurement and the measured evaluation value, the amount of change in the angle θ of the magnet unit 3 can be calculated. In this way, in the alloy thin film obtained by the second film formation after the angle θ of the magnet unit 3 is changed, the Mg composition ratio approaches the target value (for example, 8.9 vol.%).

[0131] In this way, by repeatedly performing film formation, composition analysis, and adjustment of the angle θ of the magnet unit 3 (i.e., by performing feedback control of the angle θ of the magnet unit 3 based on the composition evaluation information), an Mg-Ag alloy thin film having a target Mg composition ratio can be obtained. During a long (hundreds of hours) continuous manufacturing process, the Mg composition ratio may fluctuate over time. However, in such cases, by regularly adjusting the angle θ of the magnet unit 3 as described above, an alloy thin film having a Mg composition ratio close to the target can be stably formed over a long period of time.

[0132] Figure 16This is a graph showing the temporal change in the Mg composition ratio of the alloy thin film obtained in a long-term continuous manufacturing process. The solid line graph A shows the case where the angle θ of the magnet unit 3 is feedback controlled, and the dotted line graph B shows the case where the angle θ of the magnet unit 3 is fixed. Figure 16 As shown, when the angle θ of the magnet unit 3 is feedback-controlled, the film can be formed while maintaining the Mg composition ratio stably for a long period of time.

[0133] The interval for adjusting the angle θ of the magnet unit 3 can be adjusted for each substrate on which the film is formed, or feedback control of the angle θ of the magnet unit 3 can be performed every time a film is formed on a predetermined number of substrates (e.g., every 100 substrates). Alternatively, feedback control of the angle θ of the magnet unit 3 can be performed every time a film is formed for a predetermined period of time (e.g., every 50 hours). Furthermore, when changing the angle θ of the magnet unit 3, the film formation time and input power can be adjusted simultaneously. By adjusting the film formation time and input power, not only the Mg composition ratio but also the film thickness can be maintained constant to form a thin film.

[0134] <Example 3>

[0135] As the angle control of the magnet unit 3 based on the composition ratio information, it is conceivable to perform feed-forward control based on information on changes in the composition ratio obtained from a film formation test before the start of film formation.

[0136] In this control, the magnet unit 3 within the cylindrical target 2 is tilted at a predetermined angle (for example, 5 degrees upward from the vertical (angle θ = 5 degrees)) and a continuous film formation test is performed for a predetermined time (for example, 500 hours). During this continuous film formation test, the Mg composition ratio of the formed alloy thin film is regularly analyzed. Composition analysis can be performed using methods such as fluorescent X-ray analysis. This allows for a preliminary understanding of how the Mg composition ratio changes over time during continuous film formation using an Mg-Ag alloy target.

[0137] Next, based on the results of this preliminary test, the temporal change in the Mg composition ratio can be predicted during actual continuous film formation, and the angle θ of the magnet unit 3 can be adjusted according to the predicted Mg composition ratio. For example, if the Mg composition ratio measured after 50 hours in a preliminary test starting with an angle θ = 5 degrees and a target Mg composition ratio of 8.0 vol% is 7.6 vol%, control can be performed to adjust the angle θ of the magnet unit 3 to 10 degrees after 50 hours in actual continuous film formation. This allows the formation of thin films with a constant Mg composition ratio over long periods of continuous film formation.

[0138] Figure 17This is a graph showing the temporal change in the Mg composition ratio of a thin film obtained in a long-term continuous manufacturing process. The solid line graph A shows the case where the angle θ of the magnet unit 3 is feedforward controlled based on the Mg composition ratio predicted from the results of a previous experiment, and the dotted line graph B shows the case where the angle θ of the magnet unit 3 is fixed. Figure 17 As shown in FIG. 1 , when the angle θ of the magnet unit 3 is feed-forward controlled, the film can be formed while stably maintaining the Mg composition ratio for a long period of time.

[0139] It should be noted that in the above example, the relationship between the elapsed time of continuous sputtering film formation and the Mg composition ratio is studied through preliminary experiments and then fed forward into the angle control of the magnet unit 3 during actual film formation. However, the relationship studied through preliminary experiments is not limited to this. For example, the relationship between the cumulative number of substrates formed by continuous sputtering film formation and the Mg composition ratio can also be studied, and the angle of the magnet unit 3 can be adjusted according to the number of substrates formed during actual film formation.

[0140] <Example 4>

[0141] As the angle control of the magnet unit 3 based on the composition ratio information, it is possible to consider feedback control of the composition ratio information obtained from a measuring device provided in the film forming apparatus. The measuring device is provided, for example, at Figure 2 In the inspection chamber 105 of the in-line film forming apparatus 100 shown.

[0142] like Figure 18 As shown, an inspection region 330 for film formation for composition evaluation is provided on substrate 6 in an area separate from device region 340 of film-forming cathode 65. The inspection device in inspection chamber 105 measures the composition of the alloy thin film formed in inspection region 330 of substrate 6. This allows the Mg composition ratio of the alloy thin film formed in film-forming chamber 104 to be evaluated without affecting the thin film formed in device region 340.

[0143] The alloy thin film formed in film formation chamber 104 undergoes composition analysis in inspection chamber 105, located midway through the production line, which is always kept in a vacuum state. Based on the analysis results, the angle θ of the magnet unit 3 in sputtering apparatus 1 in film formation chamber 104 is adjusted. This allows the composition of the formed alloy thin film to be monitored during the continuous thin film production process, and the angle θ of the magnet unit 3 to be adjusted based on this information, providing feedback control of the composition. This control reduces the time lag between film formation and adjustment of the angle θ of the magnet unit 3, allowing film formation to be performed while maintaining a constant composition ratio over extended periods of production.

[0144] Example 4 can also be applied to Figure 3The film forming apparatus 111 of the group type shown in FIG. In this case, the measurement results of the Mg composition ratio in the inspection chamber 105 are fed back to the adjustment of the angle θ of the magnet unit 3 of the sputtering apparatus 1 in the film forming chamber 104 of the second group C2. It should be noted that if sputtering apparatuses with the same settings as the sputtering apparatus 1 are also installed in other groups, the measurement results of the Mg composition ratio in the inspection chamber 105 can also be fed back to the control of these sputtering apparatuses.

[0145] <Example 5>

[0146] The angle control of the magnet unit 3 based on the composition ratio information is applied to Figure 9 The case of the dual cathode sputtering device 1Y shown in FIG. Before the film forming process, the composition ratio information is calculated. Figure 11 or Figure 12 The first magnet unit 3L and the second magnet unit 3R are rotated by adjusting the angles θL and θR of the first magnet unit 3L and the second magnet unit 3R. After adjusting the angles θL and θR of the first magnet unit 3L and the second magnet unit 3R, sputtering film formation is performed while the first magnet unit 3L and the second magnet unit 3R are stationary at the adjusted angles.

[0147] exist Figure 4 Sputtering device 1, Figure 8 Sputtering device 1X, Figure 9 In the sputtering device 1Y, Figure 14 The relationship between the angle θ of the magnet unit 3 and the composition ratio of the alloy thin film to be formed does not depend on the sign of the angle θ. Figure 11 The settings and Figure 12 In the setting of , the composition ratio of the alloy film remains unchanged.

[0148] In the structure of sputtering apparatus 1Y, as described with respect to sputtering apparatus 1, the composition ratio of the alloy thin film to be formed on substrate 6 is controlled with high precision by adjusting the angles θL and θR of first and second magnet units 3L and 3R disposed within first and second targets 2L and 2R, which serve as cylindrical cathodes. Furthermore, by performing film formation multiple times while adjusting the angle θ of magnet unit 3L and second magnet unit 3R, a multilayer film with different composition ratios can be formed.

[0149] According to the control described in Examples 1 to 5 above, in magnetron rotary sputtering film formation using alloy targets with two or more compositions, the angle θ of the magnet unit 3 disposed within the target 2, which serves as a cylindrical cathode, is adjusted based on the composition ratio information of the alloy thin film formed on the substrate 6. This allows for highly precise control of the composition ratio of the alloy thin film. This allows for the formation of alloy thin films with minimal compositional variation, even during long sputtering film formation periods, reducing variations in device characteristics between substrates. This improves production yield and enables stable device fabrication over extended periods.

[0150] It should be noted that, in the magnetron rotary sputtering film formation using alloy targets of two or more components described in Examples 1 to 5, the film formation method of adjusting the angle θ of the magnet unit 3 based on the composition ratio information of the alloy thin film formed on the substrate 6, and the film formation method of forming a multilayer film with different composition ratios (having a gradient of composition ratio) in the film thickness direction by magnetron sputtering using a rotating target composed of an alloy material of two components by performing multiple film formations by changing the angle θ of the magnet unit 3 of the rotating cathode unit 8, can be applied to Figure 2 The in-line film forming apparatus 100 shown, Figure 3 The group type film forming device 111 shown, Figure 4 The substrate transport type sputtering device 1 shown, Figure 8 The sputtering device 1X of the rotary cathode unit moving type shown in FIG. Figure 9 The sputtering device 1Y of the dual cathode and rotating cathode unit moving type shown, the sputtering device of the dual cathode and substrate transport type not shown, Figure 13 The magnet unit shown is a swing-type sputtering device.

[0151] The above embodiment shows an example of the present invention, but the present invention is not limited to the structure of the above embodiment, and can also be appropriately deformed within the scope of its technical concept. For example, it is not limited to the structure in which the substrate moves relative to the rotating cathode unit fixed in the chamber, and the rotating cathode unit moves relative to the substrate fixed in the chamber. For example, the substrate and the rotating cathode unit can be fixed in the chamber, and by increasing the number of targets constituting the rotating cathode unit, the sputtering area can cover the entire film forming object area as a whole; the substrate can swing in the horizontal plane relative to the rotating cathode unit fixed in the chamber; the rotating cathode unit can swing in the horizontal plane relative to the substrate fixed in the chamber. In Figure 9 Although a dual cathode sputtering apparatus having two targets is exemplified in FIG, the number of targets may be three or more.

[0152] Description of Reference Numerals

[0153] 1: Sputtering device

[0154] 2: Target

[0155] 3: Magnet unit

[0156] 6: Substrate

[0157] 35: Rotation axis

[0158] 100: Film forming device.

Claims

1. A film forming device, comprising: a cylindrical target composed of an alloy of two or more components; and a magnetic field generating member disposed inside the target so as to be variable in angle about a rotation axis parallel to the central axis of the cylindrical shape, and generating a leakage magnetic field leaking from the outer peripheral surface of the target; The film forming device forms an alloy thin film by sputtering on a film forming object arranged to face the target while rotating the target. It is characterized by: The film forming apparatus controls the angle of the magnetic field generating member based on information on the composition ratio of the alloy thin film.

2. The film forming apparatus according to claim 1, wherein: The film forming apparatus controls the angle of the magnetic field generating member based on a composition ratio of the alloy constituting the target and a target value of a composition ratio of the alloy thin film formed on the film formation object.

3. The film forming apparatus according to claim 1, wherein: When the film formation apparatus continuously forms films on a plurality of the film formation objects, the film formation apparatus controls the angle of the magnetic field generating member based on information on the composition ratio of the alloy thin film on the film formation object previously formed.

4. The film forming apparatus according to claim 1, wherein: The film forming apparatus controls the angle of the magnetic field generating member based on information previously obtained through experiments on a temporal change in the composition ratio of the alloy thin films formed when films are continuously formed on a plurality of film formation objects.

5. The film forming apparatus according to claim 1, wherein: The film forming apparatus includes a measuring unit for measuring a composition ratio of the alloy thin film formed on the film forming object. The film forming apparatus controls the angle of the magnetic field generating member based on information on the composition ratio measured by the measuring member.

6. The film forming apparatus according to any one of claims 1 to 5, wherein: The film forming apparatus controls the angle of the magnetic field generating member based on a previously determined relationship between the angle of the magnetic field generating member and the composition ratio of the alloy thin film formed on the film formation object.

7. The film forming apparatus according to any one of claims 1 to 5, wherein: When the film forming apparatus continuously forms films on a plurality of the film formation objects, the film forming apparatus adjusts the angle of the magnetic field generating member every time the film forming apparatus forms films on a predetermined number of the film formation objects.

8. The film forming apparatus according to any one of claims 1 to 5, wherein: When the film formation apparatus continuously forms films on a plurality of the film formation objects, the film formation apparatus adjusts the angle of the magnetic field generating member every time film formation is performed for a predetermined time.

9. The film forming apparatus according to any one of claims 1 to 5, wherein: The film forming apparatus controls the angle of the magnetic field generating member so that the difference between the composition ratio of the alloy thin film and a target composition ratio is 0.5% or less.

10. The film forming apparatus according to any one of claims 1 to 5, wherein: The first component of the alloy constituting the target is Mg, and the second component is Ag.

11. The film forming apparatus according to any one of claims 1 to 5, wherein: The first component of the alloy constituting the target is any one of Li, Na, Mg, K, Ca, Cs, and Yb, and the second component is Ag or Al.

12. The film forming apparatus according to any one of claims 1 to 5, wherein: When a film is formed on the film formation object using the target, the accumulation amount distribution of the first component of the alloy constituting the target has a mountain-shaped shape having a wider width and a lower peak than the accumulation amount distribution of the second component.

13. The film forming apparatus according to claim 10, wherein: The magnetic field generating member is configured such that the composition ratio of the first component in the alloy thin film increases as the angle from the reference position increases. The film forming apparatus increases the angle of the magnetic field generating member when the composition ratio of the first component increases, and decreases the angle of the magnetic field generating member when the composition ratio of the first component decreases, based on the composition ratio of the alloy thin film.

14. The film forming apparatus according to any one of claims 1 to 5, wherein: The film forming apparatus adjusts at least one of a voltage applied to the target and a film forming time according to an angle of the magnetic field generating member.

15. The film forming apparatus according to any one of claims 1 to 5, wherein: The film forming apparatus continuously forms films on the plurality of film formation objects.

16. The film forming apparatus according to any one of claims 1 to 5, wherein: The alloy thin film constitutes the cathode of the organic EL element.

17. The film forming apparatus according to any one of claims 1 to 5, wherein: The film forming device is an in-line film forming device.

18. The film forming apparatus according to any one of claims 1 to 5, wherein: The film forming device is a group-type film forming device.

19. A film forming method using a film forming apparatus, the film forming apparatus comprising: a cylindrical target composed of an alloy of two or more components; and a magnetic field generating member disposed inside the target so as to be variable in angle about a rotation axis parallel to the central axis of the cylindrical shape, and generating a leakage magnetic field leaking from the outer peripheral surface of the target; The film forming method is characterized by: a step of forming an alloy thin film by sputtering on a film formation object disposed opposite to the target while rotating the target; and a step of controlling the angle of the magnetic field generating member based on information on the composition ratio of the alloy thin film.

20. A method for manufacturing an electronic device, characterized in that: An electronic device is manufactured using the film forming method according to claim 19.

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